621 lines
16 KiB
C
621 lines
16 KiB
C
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/*
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* pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
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* copyright (C) 1999-2019 by Willem van Schaik <willem at schaik dot com>
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*
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* This software is released under the MIT license. For conditions of
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* distribution and use, see the LICENSE file part of this package.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <fcntl.h>
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#ifndef BOOL
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#define BOOL unsigned char
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#endif
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#ifndef TRUE
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#define TRUE (BOOL) 1
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#endif
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#ifndef FALSE
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#define FALSE (BOOL) 0
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#endif
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/* make pnm2png verbose so we can find problems (needs to be before png.h) */
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#ifndef PNG_DEBUG
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#define PNG_DEBUG 0
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#endif
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#include "png.h"
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/* function prototypes */
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int main (int argc, char *argv[]);
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void usage ();
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BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file,
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BOOL interlace, BOOL alpha);
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void get_token (FILE *pnm_file, char *token_buf, size_t token_buf_size);
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png_uint_32 get_data (FILE *pnm_file, int depth);
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png_uint_32 get_value (FILE *pnm_file, int depth);
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/*
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* main
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*/
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int main (int argc, char *argv[])
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{
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FILE *fp_rd = stdin;
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FILE *fp_al = NULL;
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FILE *fp_wr = stdout;
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BOOL interlace = FALSE;
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BOOL alpha = FALSE;
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int argi;
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for (argi = 1; argi < argc; argi++)
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{
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if (argv[argi][0] == '-')
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{
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switch (argv[argi][1])
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{
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case 'i':
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interlace = TRUE;
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break;
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case 'a':
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alpha = TRUE;
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argi++;
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if ((fp_al = fopen (argv[argi], "rb")) == NULL)
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{
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fprintf (stderr, "PNM2PNG\n");
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fprintf (stderr, "Error: alpha-channel file %s does not exist\n",
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argv[argi]);
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exit (1);
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}
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break;
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case 'h':
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case '?':
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usage ();
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exit (0);
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break;
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default:
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fprintf (stderr, "PNM2PNG\n");
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fprintf (stderr, "Error: unknown option %s\n", argv[argi]);
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usage ();
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exit (1);
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break;
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} /* end switch */
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}
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else if (fp_rd == stdin)
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{
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if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
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{
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fprintf (stderr, "PNM2PNG\n");
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fprintf (stderr, "Error: file %s does not exist\n", argv[argi]);
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exit (1);
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}
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}
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else if (fp_wr == stdout)
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{
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if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
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{
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fprintf (stderr, "PNM2PNG\n");
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fprintf (stderr, "Error: cannot create PNG-file %s\n", argv[argi]);
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exit (1);
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}
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}
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else
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{
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fprintf (stderr, "PNM2PNG\n");
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fprintf (stderr, "Error: too many parameters\n");
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usage ();
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exit (1);
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}
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} /* end for */
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#if defined(O_BINARY) && (O_BINARY != 0)
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/* set stdin/stdout to binary,
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* we're reading the PNM always! in binary format
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*/
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if (fp_rd == stdin)
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setmode (fileno (stdin), O_BINARY);
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if (fp_wr == stdout)
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setmode (fileno (stdout), O_BINARY);
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#endif
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/* call the conversion program itself */
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if (pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha) == FALSE)
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{
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fprintf (stderr, "PNM2PNG\n");
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fprintf (stderr, "Error: unsuccessful converting to PNG-image\n");
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exit (1);
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}
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/* close input file */
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fclose (fp_rd);
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/* close output file */
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fclose (fp_wr);
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/* close alpha file */
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if (alpha)
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fclose (fp_al);
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return 0;
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}
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/*
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* usage
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*/
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void usage ()
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{
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fprintf (stderr, "PNM2PNG\n");
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fprintf (stderr, " by Willem van Schaik, 1999\n");
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fprintf (stderr, "Usage: pnm2png [options] <file>.<pnm> [<file>.png]\n");
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fprintf (stderr, " or: ... | pnm2png [options]\n");
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fprintf (stderr, "Options:\n");
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fprintf (stderr, " -i[nterlace] write png-file with interlacing on\n");
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fprintf (stderr,
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" -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");
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fprintf (stderr, " -h | -? print this help-information\n");
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}
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/*
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* pnm2png
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*/
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BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file,
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BOOL interlace, BOOL alpha)
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{
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png_struct *png_ptr = NULL;
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png_info *info_ptr = NULL;
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png_byte *png_pixels = NULL;
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png_byte **row_pointers = NULL;
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png_byte *pix_ptr = NULL;
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volatile png_uint_32 row_bytes;
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char type_token[16];
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char width_token[16];
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char height_token[16];
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char maxval_token[16];
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volatile int color_type = 1;
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unsigned long ul_width = 0, ul_alpha_width = 0;
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unsigned long ul_height = 0, ul_alpha_height = 0;
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unsigned long ul_maxval = 0;
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volatile png_uint_32 width = 0, height = 0;
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volatile png_uint_32 alpha_width = 0, alpha_height = 0;
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png_uint_32 maxval;
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volatile int bit_depth = 0;
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int channels = 0;
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int alpha_depth = 0;
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int alpha_present = 0;
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int row, col;
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BOOL raw, alpha_raw = FALSE;
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#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
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BOOL packed_bitmap = FALSE;
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#endif
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png_uint_32 tmp16;
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int i;
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/* read header of PNM file */
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get_token (pnm_file, type_token, sizeof (type_token));
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if (type_token[0] != 'P')
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{
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return FALSE;
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}
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else if ((type_token[1] == '1') || (type_token[1] == '4'))
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{
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#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
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raw = (type_token[1] == '4');
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color_type = PNG_COLOR_TYPE_GRAY;
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get_token (pnm_file, width_token, sizeof (width_token));
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sscanf (width_token, "%lu", &ul_width);
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width = (png_uint_32) ul_width;
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get_token (pnm_file, height_token, sizeof (height_token));
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sscanf (height_token, "%lu", &ul_height);
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height = (png_uint_32) ul_height;
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bit_depth = 1;
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packed_bitmap = TRUE;
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#else
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fprintf (stderr, "PNM2PNG built without PNG_WRITE_INVERT_SUPPORTED and\n");
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fprintf (stderr, "PNG_WRITE_PACK_SUPPORTED can't read PBM (P1,P4) files\n");
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return FALSE;
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#endif
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}
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else if ((type_token[1] == '2') || (type_token[1] == '5'))
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{
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raw = (type_token[1] == '5');
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color_type = PNG_COLOR_TYPE_GRAY;
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get_token (pnm_file, width_token, sizeof (width_token));
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sscanf (width_token, "%lu", &ul_width);
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width = (png_uint_32) ul_width;
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get_token (pnm_file, height_token, sizeof (height_token));
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sscanf (height_token, "%lu", &ul_height);
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height = (png_uint_32) ul_height;
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get_token (pnm_file, maxval_token, sizeof (maxval_token));
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sscanf (maxval_token, "%lu", &ul_maxval);
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maxval = (png_uint_32) ul_maxval;
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if (maxval <= 1)
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bit_depth = 1;
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else if (maxval <= 3)
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bit_depth = 2;
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else if (maxval <= 15)
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bit_depth = 4;
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else if (maxval <= 255)
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bit_depth = 8;
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else if (maxval <= 65535U)
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bit_depth = 16;
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else /* maxval > 65535U */
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return FALSE;
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}
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else if ((type_token[1] == '3') || (type_token[1] == '6'))
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{
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raw = (type_token[1] == '6');
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color_type = PNG_COLOR_TYPE_RGB;
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get_token (pnm_file, width_token, sizeof (width_token));
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sscanf (width_token, "%lu", &ul_width);
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width = (png_uint_32) ul_width;
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get_token (pnm_file, height_token, sizeof (height_token));
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sscanf (height_token, "%lu", &ul_height);
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height = (png_uint_32) ul_height;
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get_token (pnm_file, maxval_token, sizeof (maxval_token));
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sscanf (maxval_token, "%lu", &ul_maxval);
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maxval = (png_uint_32) ul_maxval;
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if (maxval <= 1)
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bit_depth = 1;
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else if (maxval <= 3)
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bit_depth = 2;
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else if (maxval <= 15)
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bit_depth = 4;
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else if (maxval <= 255)
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bit_depth = 8;
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else if (maxval <= 65535U)
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bit_depth = 16;
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else /* maxval > 65535U */
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return FALSE;
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}
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else
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{
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return FALSE;
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}
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/* read header of PGM file with alpha channel */
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if (alpha)
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{
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if (color_type == PNG_COLOR_TYPE_GRAY)
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color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
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if (color_type == PNG_COLOR_TYPE_RGB)
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color_type = PNG_COLOR_TYPE_RGB_ALPHA;
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get_token (alpha_file, type_token, sizeof (type_token));
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if (type_token[0] != 'P')
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{
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return FALSE;
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}
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else if ((type_token[1] == '2') || (type_token[1] == '5'))
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{
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alpha_raw = (type_token[1] == '5');
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get_token (alpha_file, width_token, sizeof (width_token));
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sscanf (width_token, "%lu", &ul_alpha_width);
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alpha_width = (png_uint_32) ul_alpha_width;
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if (alpha_width != width)
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return FALSE;
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get_token (alpha_file, height_token, sizeof (height_token));
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sscanf (height_token, "%lu", &ul_alpha_height);
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alpha_height = (png_uint_32) ul_alpha_height;
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if (alpha_height != height)
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return FALSE;
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get_token (alpha_file, maxval_token, sizeof (maxval_token));
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sscanf (maxval_token, "%lu", &ul_maxval);
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maxval = (png_uint_32) ul_maxval;
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if (maxval <= 1)
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alpha_depth = 1;
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else if (maxval <= 3)
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alpha_depth = 2;
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else if (maxval <= 15)
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alpha_depth = 4;
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else if (maxval <= 255)
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alpha_depth = 8;
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else if (maxval <= 65535U)
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alpha_depth = 16;
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else /* maxval > 65535U */
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return FALSE;
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if (alpha_depth != bit_depth)
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return FALSE;
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}
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else
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{
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return FALSE;
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}
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} /* end if alpha */
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/* calculate the number of channels and store alpha-presence */
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if (color_type == PNG_COLOR_TYPE_GRAY)
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channels = 1;
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else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
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channels = 2;
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else if (color_type == PNG_COLOR_TYPE_RGB)
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channels = 3;
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else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
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channels = 4;
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#if 0
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else
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channels = 0; /* cannot happen */
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#endif
|
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alpha_present = (channels - 1) % 2;
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#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
|
||
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if (packed_bitmap)
|
||
|
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{
|
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|
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/* row data is as many bytes as can fit width x channels x bit_depth */
|
||
|
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row_bytes = (width * channels * bit_depth + 7) / 8;
|
||
|
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}
|
||
|
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else
|
||
|
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#endif
|
||
|
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{
|
||
|
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/* row_bytes is the width x number of channels x (bit-depth / 8) */
|
||
|
|
row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
|
||
|
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}
|
||
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|
||
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if ((row_bytes == 0) ||
|
||
|
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((size_t) height > (size_t) (-1) / (size_t) row_bytes))
|
||
|
|
{
|
||
|
|
/* too big */
|
||
|
|
return FALSE;
|
||
|
|
}
|
||
|
|
if ((png_pixels = (png_byte *)
|
||
|
|
malloc ((size_t) row_bytes * (size_t) height)) == NULL)
|
||
|
|
{
|
||
|
|
/* out of memory */
|
||
|
|
return FALSE;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* read data from PNM file */
|
||
|
|
pix_ptr = png_pixels;
|
||
|
|
|
||
|
|
for (row = 0; row < (int) height; row++)
|
||
|
|
{
|
||
|
|
#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
|
||
|
|
if (packed_bitmap)
|
||
|
|
{
|
||
|
|
for (i = 0; i < (int) row_bytes; i++)
|
||
|
|
{
|
||
|
|
/* png supports this format natively so no conversion is needed */
|
||
|
|
*pix_ptr++ = get_data (pnm_file, 8);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
#endif
|
||
|
|
{
|
||
|
|
for (col = 0; col < (int) width; col++)
|
||
|
|
{
|
||
|
|
for (i = 0; i < (channels - alpha_present); i++)
|
||
|
|
{
|
||
|
|
if (raw)
|
||
|
|
{
|
||
|
|
*pix_ptr++ = get_data (pnm_file, bit_depth);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
if (bit_depth <= 8)
|
||
|
|
{
|
||
|
|
*pix_ptr++ = get_value (pnm_file, bit_depth);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
tmp16 = get_value (pnm_file, bit_depth);
|
||
|
|
*pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
|
||
|
|
pix_ptr++;
|
||
|
|
*pix_ptr = (png_byte) (tmp16 & 0xFF);
|
||
|
|
pix_ptr++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if (alpha) /* read alpha-channel from pgm file */
|
||
|
|
{
|
||
|
|
if (alpha_raw)
|
||
|
|
{
|
||
|
|
*pix_ptr++ = get_data (alpha_file, alpha_depth);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
if (alpha_depth <= 8)
|
||
|
|
{
|
||
|
|
*pix_ptr++ = get_value (alpha_file, bit_depth);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
tmp16 = get_value (alpha_file, bit_depth);
|
||
|
|
*pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
|
||
|
|
*pix_ptr++ = (png_byte) (tmp16 & 0xFF);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
} /* end if alpha */
|
||
|
|
} /* end if packed_bitmap */
|
||
|
|
} /* end for col */
|
||
|
|
} /* end for row */
|
||
|
|
|
||
|
|
/* prepare the standard PNG structures */
|
||
|
|
png_ptr = png_create_write_struct (png_get_libpng_ver(NULL),
|
||
|
|
NULL, NULL, NULL);
|
||
|
|
if (!png_ptr)
|
||
|
|
{
|
||
|
|
free (png_pixels);
|
||
|
|
return FALSE;
|
||
|
|
}
|
||
|
|
info_ptr = png_create_info_struct (png_ptr);
|
||
|
|
if (!info_ptr)
|
||
|
|
{
|
||
|
|
png_destroy_write_struct (&png_ptr, NULL);
|
||
|
|
free (png_pixels);
|
||
|
|
return FALSE;
|
||
|
|
}
|
||
|
|
|
||
|
|
#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
|
||
|
|
if (packed_bitmap == TRUE)
|
||
|
|
{
|
||
|
|
png_set_packing (png_ptr);
|
||
|
|
png_set_invert_mono (png_ptr);
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
if (setjmp (png_jmpbuf (png_ptr)))
|
||
|
|
{
|
||
|
|
png_destroy_write_struct (&png_ptr, &info_ptr);
|
||
|
|
free (png_pixels);
|
||
|
|
return FALSE;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* initialize the png structure */
|
||
|
|
png_init_io (png_ptr, png_file);
|
||
|
|
|
||
|
|
/* we're going to write more or less the same PNG as the input file */
|
||
|
|
png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth, color_type,
|
||
|
|
(!interlace) ? PNG_INTERLACE_NONE : PNG_INTERLACE_ADAM7,
|
||
|
|
PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
|
||
|
|
|
||
|
|
/* write the file header information */
|
||
|
|
png_write_info (png_ptr, info_ptr);
|
||
|
|
|
||
|
|
/* if needed we will allocate memory for an new array of row-pointers */
|
||
|
|
if (row_pointers == NULL)
|
||
|
|
{
|
||
|
|
if ((row_pointers = (png_byte **)
|
||
|
|
malloc (height * sizeof (png_byte *))) == NULL)
|
||
|
|
{
|
||
|
|
png_destroy_write_struct (&png_ptr, &info_ptr);
|
||
|
|
free (png_pixels);
|
||
|
|
return FALSE;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* set the individual row_pointers to point at the correct offsets */
|
||
|
|
for (i = 0; i < (int) height; i++)
|
||
|
|
row_pointers[i] = png_pixels + i * row_bytes;
|
||
|
|
|
||
|
|
/* write out the entire image data in one call */
|
||
|
|
png_write_image (png_ptr, row_pointers);
|
||
|
|
|
||
|
|
/* write the additional chunks to the PNG file (not really needed) */
|
||
|
|
png_write_end (png_ptr, info_ptr);
|
||
|
|
|
||
|
|
/* clean up after the write, and free any memory allocated */
|
||
|
|
png_destroy_write_struct (&png_ptr, &info_ptr);
|
||
|
|
|
||
|
|
if (row_pointers != NULL)
|
||
|
|
free (row_pointers);
|
||
|
|
if (png_pixels != NULL)
|
||
|
|
free (png_pixels);
|
||
|
|
|
||
|
|
return TRUE;
|
||
|
|
} /* end of pnm2png */
|
||
|
|
|
||
|
|
/*
|
||
|
|
* get_token - gets the first string after whitespace
|
||
|
|
*/
|
||
|
|
|
||
|
|
void get_token (FILE *pnm_file, char *token_buf, size_t token_buf_size)
|
||
|
|
{
|
||
|
|
size_t i = 0;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
/* remove white-space and comment lines */
|
||
|
|
do
|
||
|
|
{
|
||
|
|
ret = fgetc (pnm_file);
|
||
|
|
if (ret == '#')
|
||
|
|
{
|
||
|
|
/* the rest of this line is a comment */
|
||
|
|
do
|
||
|
|
{
|
||
|
|
ret = fgetc (pnm_file);
|
||
|
|
}
|
||
|
|
while ((ret != '\n') && (ret != '\r') && (ret != EOF));
|
||
|
|
}
|
||
|
|
if (ret == EOF) break;
|
||
|
|
token_buf[i] = (char) ret;
|
||
|
|
}
|
||
|
|
while ((ret == '\n') || (ret == '\r') || (ret == ' '));
|
||
|
|
|
||
|
|
/* read string */
|
||
|
|
do
|
||
|
|
{
|
||
|
|
ret = fgetc (pnm_file);
|
||
|
|
if (ret == EOF) break;
|
||
|
|
if (++i == token_buf_size - 1) break;
|
||
|
|
token_buf[i] = (char) ret;
|
||
|
|
}
|
||
|
|
while ((ret != '\n') && (ret != '\r') && (ret != ' '));
|
||
|
|
|
||
|
|
token_buf[i] = '\0';
|
||
|
|
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* get_data - takes first byte and converts into next pixel value,
|
||
|
|
* taking as much bits as defined by bit-depth and
|
||
|
|
* using the bit-depth to fill up a byte (0Ah -> AAh)
|
||
|
|
*/
|
||
|
|
|
||
|
|
png_uint_32 get_data (FILE *pnm_file, int depth)
|
||
|
|
{
|
||
|
|
static int bits_left = 0;
|
||
|
|
static int old_value = 0;
|
||
|
|
static int mask = 0;
|
||
|
|
int i;
|
||
|
|
png_uint_32 ret_value;
|
||
|
|
|
||
|
|
if (mask == 0)
|
||
|
|
for (i = 0; i < depth; i++)
|
||
|
|
mask = (mask >> 1) | 0x80;
|
||
|
|
|
||
|
|
if (bits_left <= 0)
|
||
|
|
{
|
||
|
|
old_value = fgetc (pnm_file);
|
||
|
|
bits_left = 8;
|
||
|
|
}
|
||
|
|
|
||
|
|
ret_value = old_value & mask;
|
||
|
|
for (i = 1; i < (8 / depth); i++)
|
||
|
|
ret_value = ret_value || (ret_value >> depth);
|
||
|
|
|
||
|
|
old_value = (old_value << depth) & 0xFF;
|
||
|
|
bits_left -= depth;
|
||
|
|
|
||
|
|
return ret_value;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* get_value - takes first (numeric) string and converts into number,
|
||
|
|
* using the bit-depth to fill up a byte (0Ah -> AAh)
|
||
|
|
*/
|
||
|
|
|
||
|
|
png_uint_32 get_value (FILE *pnm_file, int depth)
|
||
|
|
{
|
||
|
|
static png_uint_32 mask = 0;
|
||
|
|
char token[16];
|
||
|
|
unsigned long ul_ret_value;
|
||
|
|
png_uint_32 ret_value;
|
||
|
|
int i = 0;
|
||
|
|
|
||
|
|
if (mask == 0)
|
||
|
|
for (i = 0; i < depth; i++)
|
||
|
|
mask = (mask << 1) | 0x01;
|
||
|
|
|
||
|
|
get_token (pnm_file, token, sizeof (token));
|
||
|
|
sscanf (token, "%lu", &ul_ret_value);
|
||
|
|
ret_value = (png_uint_32) ul_ret_value;
|
||
|
|
|
||
|
|
ret_value &= mask;
|
||
|
|
|
||
|
|
if (depth < 8)
|
||
|
|
for (i = 0; i < (8 / depth); i++)
|
||
|
|
ret_value = (ret_value << depth) || ret_value;
|
||
|
|
|
||
|
|
return ret_value;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* end of source */
|